Windows 7: Dazed And Confused By BSOD Problem

2 bootable win 7 HP 64 bit. After booting back and forth for a nonth with no problem now when I boot into the second partition and exit to go back to the first I get a BSOD. Safe mode works. RAM tests ok. So does check disk. Full av scan shows nothing wrong. Tried system restore as well as registry back up but only after a dozen attempts or so am I able to finally boot up normally. Pissed and Puzzled in Las Vegas. Thank you


Additional Info

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Filename : PSHED.dll
Address In Stack :
From Address : fffff880`00cbf000
To Address : fffff880`00cd3000
Size : 0x00014000
Time Stamp : 0x4a5be027
Time String : 7/13/2009 5:32:23 PM
Product Name : Microsoft® Windows® Operating System
File Description : Platform Specific Hardware Error Driver
File Version : 6.1.7600.16385 (win7_rtm.090713-1255)
Full Path : C:\Windows\system32\PSHED.dll
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Filename : ntoskrnl.exe
Address In Stack :
From Address : fffff800`02c49000
To Address : fffff800`03225000
Size : 0x005dc000
Time Stamp : 0x4c1c44a9
Time String : 6/18/2010 8:16:41 PM
Product Name : Microsoft® Windows® Operating System
File Description : NT Kernel & System
File Version : 6.1.7600.16617 (win7_gdr.100618-1621)
Full Path : C:\Windows\system32\ntoskrnl.exe

Problem signature:
Problem Event Name: BlueScreen
OS Version: 6.1.7600.2.0.0.768.3
Locale ID: 1033



Additional information about the problem:
BCCode: 1000007e
BCP1: FFFFFFFFC0000005
BCP2: FFFFF88001AB7BB8
BCP3: FFFFF88003B51838
BCP4: FFFFF88003B510A0
OS Version: 6_1_7600
Service Pack: 0_0
Product: 768_1